Electric switch



Jan. 3, 1939. R. F. SAMBLESON ELECTRIC SWITCH Filed Nov. 15, 1935 5 Sheets-Sheet 1 I n ventorm 5 mM a F 5 0w Fat m e s R 9 Jan. 3, 1939. R. F. SAMBLESON ELECTRIC SWITCH Filed Nov. 15, 1955 3 Sheets-Sheet 2 a WWW Inventor: Robert, E Samblesoh,

is Attorne R. F. SAMBLESON ELECTRIC SWITCH Jan. 3, 1939.

Filed Nov. 15, 1955 3 Sheets-Sheet 3 Patented Jan. 3, i939 ELECTRIC swrrcn Robert F. Sambleson, Bridgeport, Conn, assignor to General Electric Company, a corporation of New York Application November 15, 1935, Serial No. 4!);927

26 Claims. (01. 200-153) K The present invention relates to electric switches of the type having liquid contact circuit closers for controlling the flow of current.

The object of my invention is to provide an improved construction and arrangement in a switch of this type, and for a consideration of what I believe to be novel and my invention attention is I directed to'the accompanying description and the claims appended thereto. In the accompanying'drawings, Fig. 1 is a sectional side elevation taken on line I--l of Fig. 2 of a switchembodying my invention; Fig. 2 is a plan view partially broken away of the switch shown in Fig. 1; Fig. 3 is a sectional view taken on line 3-3 of Fig. 1; Fig. 4 is a diagrammatic view showing the construction and operation of the liquid contact circuit closer; Fig. 5 is a sectional side elevation taken on line 55 of Fig. 6 showing a modification of the switch embodying my invention; Fig. 6 is a plan view partly broken away of the switch shown in Fig. 5; Fig. 'I is a sectional view taken on line 1-1 of Fig. 5; Fig. 8 is a sectional view taken on line 8-8 of Fig. 6; Fig. 9 is a sectional side elevation taken on line 99 of Fig. 10 and showing another modification of my invention; Fig. 10 is a plan view partly broken away of the switch shown in Fig. 9; Fig. 11 is a sectional view taken on line I- -l of Fig. 9; Fig. 12 is a diagrammatic view showing the circult connections of the switch; and Fig. 13 is a diagrammatic view showing a modificaton of the circuit connections'of the switch.

Referring to Figs. 1 to 4 inclusive, I have illustrated my invention using a liquid contact cir cult closer having a pair of cup-shaped metal terminals I which are separated by an insulating diaphragm 2 of refractory materialgsuch'as a ceramic material. The edges of the terminals are I sealed by a bead 3 of glass which also seals the 0 junction between the diaphragm and the terminals. Within the space enclosed by the terminals is a suitable quantity of mercury 4 which forms the conducting medium between the terminals. In the manufacture of the circuit closer, the space enclosed by the terminals is evacuated and filled with hydrogen at -a pressure of one .or more atmospheres which increases the current interruptingcapacity of the circuit closer. As shown by the iu'l lines in Fig. 4, the diaphragm'Z is pro- 20 vided withan opening 5 which is submerged in the mercury when the circuit closer is in the current conducting position. When the circuit closer is in the current interrupting position shown in dotted lines in Fig. 4, the opening 5 is above the mercury, and the circuit between the terminals is therefore interrupted by the insulating diaphragm 2. Due to the construction of the circuit closer, the interruption of the circuit between the terminals takes place in the mercury as the circuit closer isturned so that the opening 5 in the diaphragm approaches the dotted line position. The above-described construction is typical' of a liquid contact circuit closer which is suitable for use in a switch embodying my invention. l 10 The liquid contact circuit closer is carried within a housing 6 of a suitable molded insulating materal. At the bottom of the housing are bosses 1 which engage the periphery of the circuit closer at angularly spaced points. The bosses l are 15 grooved to conform with the outer surface of the circuit closer, and the grooves prevent lateral displacement of the circuit closer and also provide supports in which the circuit closer is cradled. On either side of the circuit closer are 20 contacts 8 which rest on the bottom wall of the housing 6 and are held against lateral displacement by slots 9 adjacent the side walls of the housing. Theportions of the contacts 8 adjacent the terminals l are provided with circular pro-. 25 jections I0 which fit into a complementary depression H in each of the terminals. The portions In and provide a ball and socket connection between the contacts 8 and the terminals and therefore provide a construction which permits 30 rotation of the liquid contact circuit closer about its axis. During the rotation of the circuit closer, the wiping action between the terminals and the contacts tends to prevent increase of contact resistance. The same support for the circuit closer 5 7 would be provided if the projections H) were formed on the terminals l and the depressions l l were formed in the contacts 8. At the other end of the contacts 8 are provided terminal screws l2 which are threaded into nuts 13 and which are adapted to clamp the line conductors to the contacts 8. The bottom wall of the base is provided with open-ended slots I4 for receiving the ends of the terminal screws l2 and open-ended slots and prevents lateraldisplacement of the handle relative to the circuit closer. On thevunder' side of the handle are projections l8 which ilt in depressions IS in the terminals l and prevent relative rotation between the handle and the circuit closer. The handle is held in place by a pair of spring strips 26 which engage the curved surfaces ti on either side of the handle. On the surfaces ill of the handle are projections 22 which cooperate with indentations 23 in the spring strips and resiliently hold the handle in either of its extreme positions. It is apparent that the springs 29 will bias the handle to either extreme position. Also, the indentations 23 cushion the movement or the handle so that the movement of the handle to either extreme position is not accompanied by a sharp noise due to the impact of the handle with a stationary part. The spring strips 28 are riveted to a support or mounting strap is which is secured to the housing 6 by means of drive screws 25. The mounting strap provides a means for mounting the switch in an outlet box. When so mounted, the right-hand end of the mounting strap 24 should be at the top of the outlet box.

Besides holding the handle iii in place on the liquid contact circuit closer, the spring strips 26 also force the circuit closer toward the bottom of the housing 6. Due to the socket connection provided between the contacts 8 and the terminals i, this downward force increases the contact pressure between the contacts 8 and the terminals I. Since the contacts 8 are adjacent the side walls of the housing, spreading of the contacts is prevented, and this force does not displace the contacts relative to the terminals. In order to further increase the contact pressure between the terminals and the contacts 8, the contacts are formed so that the ends adjacent the terminals curve inward and the resistance of the contacts therefore increases the contact pressure.

In the assembly of the switch, the terminal screws 12 are attached to the contacts 8 by means of the nuts l3. The projecting portions ID of the contacts are then placed within the depressions H in the terminals I. The handle IB is then placed on the liquid contact circuit closer so that the projections 8 of the handle fits within the depressions IS in the terminals. The assembled parts are then inserted through the open end of the housing, and the mounting strap 24 is attached to the housing holding the parts in assembled relation.

In the use of the switch, the switch is mounted in an outlet box by means of the mounting strap 24, the right-hand end of the mounting strap being located at the top of the outlet box. When so mounted, vertical movement of the handle l6 causes the liquid contact circuit closer to be rotated about its axis. When the handle [6 is in the raised position, as shown in full lines in Fig. 4,-the opening 5 in the diaphragm 2 is submerged in the mercury, and an electric circuit is completed between the terminals I through the mercury. When the handle is in the lowered position, as shown in dotted lines in Fig. 4, the opening 5 is raised out of the mercury, and the circuit between the terminals l is broken. The handle is resiliently held in either the raised or the lowered positions by the engagement of the projections 22 with the depressions 23 of the spring strips 20. It is apparent that by changing the location of the opening 5 in the diaphragm 2, or by changing the position of the depressions IS, the switch can be adapted for mounting in other than vertical positions.

The switch shown in Figs. 5 to 8 inclusive uses the liquid contact circuit closer shown in Fig. 4,

3i into which is threaded a terminal screw 32- for clamping the line conductors to the contact. The housing is provided with a hole 33 which provides sufiicient clearance so that the terminal screw may be threaded into the contact. This construction is clearly shown in Fig. 8. The contacts 2'! are clamped against the bottom of the housing 26 by strips 34 of insulating material which are placed between the mounting strap 24 and the upper surface of the contacts. The construction of the mounting strap 24 and the handle i6 is substantially the same as that used in the switch shown in Figs. 1 to 4 inclusive. However, in the switch shown in Figs. 5 to 8 inclusive, the mounting strap is secured to the top of the housing by screws 35 which are threaded through the bottom of the housing. As shown in Fig. 6, one side of each of the strips 34 engages the end wall 36 of the housing, and the other side of the strips 34 engages the end 31 of one of the side walls of the housing. The strips 34 are therefore prevented from twisting when the mounting strapiis secured to the housing. With this arrangement, the contacts are securely held in place in the housing, and the mounting strap is securely held to the housing without the use of inserts molded into the housing.

In the assembly of the switch, the contacts 21 are assembled on either side of the liquid contact circuit closer so that the projections 28 fit within the depressions 29 in the terminals l. During assembly, the ends of the contacts 21 adjacent the terminals may be bent inwardly so as to increase the contact pressure. The handle I6 is then placed on the circuit closer so that projections I 8 fit within depressions IS in the terminals, and the assembled parts are inserted into the housing 26. The strips 24 are then placed on the contacts, and the mounting strap is secured to the top of the housing by the screws 25, thereby holding the parts in assembled relation. A cover plate 310 may be attached to the mounting strap by screws 21b.

The operation of this switch is the same as the switch shown in Figs. 1 to 4 inclusive.

In Figs. Ste 12 inclusive is shown a doublepole switch using two liquid contact circuit closers of the construction shown in Fig. 4. These circuit closers are supported in a housing 38 of molded insulating material by two pairs of contacts 39 which are provided with circular projections 40 fitting within complementary demos-.-

sions 4| in the terminals of the circuit closers. One end of each of the contacts is secured to the housing by the spun-over portion 42 of a tubular insert 43 molded into the housing. A terminal screw 44 is threaded into the insert 43. The low er edge ofthe contacts 29 rest on shoulders 444 on the housing. These shoulders are not essential since the contacts are supported in the housing by means of the spun-over portion 42 of the inserts 42 and, since the socket portions provided by the projections 40 and the complementary recesses 4| provide a support for the liquid contact circuit closers in addition to permitting relative rotation between the contacts and the ter--' minals of the circuit closers. As in the previous constructions, spreading of the contacts 39 is limited by the walls of the housing so that the liquid contact circuit closers are securely held in place within the housing. For operatlng the circuit closers I have provideda handle 45 which can be identical with the handle IS. The handle 45 has curved flanges 46 on either side thereof which fit over the periphery of the inner terminals of the circuit closers. For locating the handle with reference to the circuit closers, projections 47 are provided on flanges 46 which fit into complementary notches 48 formed in the terminals. As in the previous constructions, the handle 45 is held in place on the liquid contact circuit closers by spring strips 49 which engage a projection 50 on each of the curved surfaces 46 of the handle. From the nature of this construction, the pressure of the spring strips 49 on the projections iifl tend to bias the handle to either extreme position. The spring strips 49 are riveted to a mounting strap which is secured to the top of the housing by screws 52. A dust cover 53 is carried by the mounting strap 5!,

In the assembly of the switch, the contacts 39 are assembled on each side of the liquid contact circuit closers so that the projections 40 fit within the depressions 4! in the terminals. The circuit closers and contacts are then inserted within the housing, and the contacts are secured to the housing by spinning the portions 42 of the inserts 33 over the contacts 39. The liquid contact circuit closers now being assembled withid'the housing, the handle 45 is then placed on the circuit closers so that the projections 41 fit within the depressions 48. The dust cover 53 is then inserted between the springs 49 and the mounting strap 5!, and the mounting strap is dropped In the use of the switch, the switch is mounted in an outlet box so that the right-hand end of the mounting strap is at the top of the outlet box. The circuit connections for the switch are shown diagrammatically in Fig. 12. Both of the liquid contact circuit closers are identical and it is apparent from these connections that when the handle is in the raised position, the circuit is completed from terminal A to terminal B and from terminal C to terminal D. i When the handle is in the lowered position, both of these circuits are broken.

In FigiS I have shown a circuit arrangement by means of which the switch may be used as a three-way switch. In this arrangement, the terminals A and C are electrically connected, and the construction of the liquid contact circuit closers is such that when the'handle 45 is in the raised position the circuit is completed from the terminals A and C to the terminal B, and the circuit is open from the terminals A and C to the terminal D. When the handle is in the lowered position, the circuit is completed from the terminals A and C to the terminal D, andthe circuit is open from the terminals A and C to the terminal. B. l.

By making suitable changes in the construction of the liquid contact circuit closers or in the arrangements for locating the handle with reference to these circuit closers, the switch may be arranged for mounting in other than the vertical position.

' axis of What I claim as new and desire to secure by ing opposed surfaces, and a liquid contact circuit closer between said contacts and having terminals frictionally engaging said opposed surfaces, said terminals and said opposed surfaces having complementary ball and socket portions whereby said circuit closer is rotatable about the axis of its terminals, theconta-cting .surfaces of said portionsbeing inclined with respect to the axis of rotation of the circuit closer.

2. In an electric switch, spaced contacts having opposed surfaces, at liquid contact circuit closerbetween said contacts and having terminals frictionally engaging said opposed, surfaces, said terminals and said opposed surfaces having complementary ball and socket portions whereby said circuit closer is rotatable about the axis of its terminals, the contacting surfaces of said portions being inclined with respect to the axis of rotation of the circuit closer, and means preventing spreading of said contacts for holding said circuit closer between said contacts.

3. In an electric switch, spaced contacts having opposed surfaces, a liquid contact circuit closer between said contacts and having terminals frictionally engaging said opposed surfaces, said terminals andsaid opposed surfaces having complementary ball and socket portions whereby said circuit closer is rotatable about the its terminals, means for preventing spreading of said contacts, and means exerting a force on said circuit closer transversely to its axis for maintaining contact pressure between said terminals and said contacts.

4. In an electric switch, spaced contacts having opposed surfaces, a liquid contact circuit closer between said contacts and having terminals frictionally engaging said opposed surfaces, said terminals and said opposed surfaces having complementary ball and socket portions whereby said circuit closer is rotatable about the axis of its terminals, a housing for said switch having walls for preventing spreading of said contacts and provided with means for supporting said contacts, and means secured to said housing for exerting a force on said circuit closer transcloser having an enclosure including opposed cup-shaped terminals, and contacts engaging said terminals, said contacts and said terminals having complementary projections and depressions formed therein whereby said circuit closer is supported for rotation about the axis of its terminals.

, '7. In an electric switch, aliquid contact circuit closer having an enclosure including opposed cup-shaped terminals, contacts engaging said terminals, said contacts and said terminals having complementary projections and depressions formed therein whereby said circuit closer is supported for rotation about the axis of its terminals, the contacting surfaces of said projections and depressions being inclined to the axis of rotation of the circuit closer, and means exerting a force on said circuit closure transversely to its axis for maintaining the contact pressure between said terminals and said contacts.

8. In an electric switch, a liquid contact circuit closer having an enclosure including opposed cup-shaped terminals, contacts engaging said terminals, said contacts and said terminals having complementary projections and depressions formed therein whereby said circuit closer is supported for rotation about the axis of its terminals, a handle fitting over less than half the periphery of said terminals, said handle and said terminals having interfltting portions for preventing relative rotation therebetween, arcuate flanges extending from each side of said handle,

and spring strips engaging said flanges for holdbead therebetween, means for supporting said circuit closer for rotation about the axis of its terminals, a handle fitting over less than half the periphery of said bead and said terminals, said handle and said terminals having interfltting portions for preventing relative rotation therebetween, arcuate flanges extending from each side of said handle, and spring strips engaging said flanges for holding said handle on said terminals.

10. In an electric switch, a housing, a liquid contact circuit closer having an enclosure including opposed cup-shaped terminals, means for supporting said circuit closer in said housing for rotation about the axis of its terminals, a handle fitting over less than half the periphery of said terminals, said handle and said terminals having interfitting portions for preventing relative rotation therebetween, arcuate flanges extending from each side of said handle, a plate secured to said housing and having an opening therein through which said handle projects, and spring strips carried by said plate and engaging said flanges for holding said handle on said terminals.

11. In an electric switch, a liquid contact circuit closer having a liquid containing envelope including opposed terminals of sheet metal, sheet metal contacts engaging said terminals, and complementary projections and depressions in said terminals and said contacts'providing engaging bearing surfaces whereby the circuit closer is rotatable about the axis of its terminals, said bearing surfaces being of relatively great diameter compared to the thickness of the metal.

12. In an electric switch, a liquid contactcircuit closer having opposed terminals, and contaots engaging said terminals, saidterminals and said contacts having hollow thin-walled projections providing inter-engaging bearing surfaces whereby the circuit closer is supported for rotation the diameter of said bearing surfaces being relatively great compared to the wall thicknessof said projections.

13. In an electric switch, a liquid contact circuit closer having opposed terminals, said ter-. minals providing bearing surfaces extending axially along the axis of rotation of the circuit closer, and contacts having thin walled projections engaging said bearing surfaces whereby the circuit closer is supported for rotation, the diameter of said bearing surfaces being relativelygreat compared to the wall thickness of said projections.

14. In an electric switch, a liquid contact circuit closer having opposed terminals of sheet metal, sheet metal contacts engaging said terminals, complementaryprojections and depressions in said terminals and said contacts providing engaging bearing surfaces whereby the circuit closer is rotatable about the axes of its terminals, said'bearing surfaces being of relatively great diameter compared to the thickness of the sheet metal and being inclined to the axis of rotation of the circuit closer, and means exerting a force tending to wedge said inclined surfaces together whereby the contact pressure therebetween is increased.

15. In an electric switch, spaced contacts having opposed surfaces, a liquid contact circuit closer between said contacts and having terminals frictionally engaging said opposed surfaces, said surfaces and said terminals having interfitting projections and depressions providing engaging bearing surfaces whereby the circuit closer is supported for rotation about the axis of its terminals, said surfaces being inclined to the axis of rotation of the circuit closer whereby a force exerted on the circuit closer transverse to its axis of rotation tends to wedge the contacts apart, means exerting a force on the circuit closer transverse to its axis of rotation, and a housing for said switch having walls preventing spreading of said contacts.-

16. In an electric switch, a liquid contact circuit closer having opposed terminals, contacts engaging said terminals, said terminals and said contacts having interengaging thin-walled bearing surfaces whereby the circuit closer is sup ported for rotation about the axis of its terminals, the diameter of said bearing surfaces being relatively great compared to' the wall thickness of said surfaces.

17. In an electric switch, a cylindrical liquid contact circuit closer of the type operable by rotation about its axis, a structure including means for supporting the circuit closer for rotation, a handle fitting over less than half the periphery of said circuit closer, said handle and said circuit closer having interfltting portions whereby relative rotation therebetween is prevented, and a member secured to said supporting means and engaging said handle for holding the handle on the circuit closer, said member having an opening through which said handle projects.

18. In an electric switch, a. housing having a side wall provided with an opening adjacent one end, a. contact strip adjacent and extending longitudinally of said wall, said strip being provided with means for attaching a conductor thereto accessible through said opening, and a liquid contact circuit closer having a terminal engaging said contact strip, said contact strip and said terminal having interfltting bearing surfaces .whereby the circuit closer is rotatable about an by the, circuit closer is supported for rotation.

about the axis of its terminals, a housing having walls adjacent said'contacts holding said contacts against said terminals and having surfaces on which the contacts rest, and means including a member secured to the housing for clamping said contacts against said surfaces for holding the said terminals having inter-fitting portions whe'reby the circuit closer is supported for rotation about the axis of its terminals, a housing having walls adjacent said contacts holding said contacts against said terminals and having surfaces on which the contacts rest, and means exerting a force on said circuit closer transversely to the axis of its terminals for holding the contacts against said surfaces whereby the contacts and circuit closer are held in the housing.

21. In an electricswitch, spaced contacts having opposed surfaces, 9, liquid contact circuit closer between said contacts and having terminals engaging said opposed surfaces, said contacts and said terminals having interfltting portions whereby the circuit closer is supported for rotation about the axis of its terminals, a housing having walls adjacent said contacts holding said contacts against said terminals and having surfaces on which the contacts rest, a handle on the circuit closer for rotating the circuit closer, and resilient means exerting a force on said handle. transversely to the axis of its terminals whereby the contacts are clamped against said surfaces and the circuit closer and contacts are held in the housing.

22. In an electric switch, spaced contacts having opposed surfaces, a liquid contact circuit closer between said contacts and having terminals engaging said opposed surfaces, said contacts and said terminals having interfitting portions whereby the circuit closer is supported for rotation about the axis of its terminals, a housing having walls adjacent said'contacts holding said contacts against said terminals and having surfaces on which the contacts rest, a handle on the circuit! closer for rotating the circuit closer, a member secured to the housing through which the handle projects, and spring means arranged between the handle and the member for exerting a force on the 23. In an electric switch,.a housing having side walls provided with openings and having bosses outside of said openings facing the top of the housing, contact strips adjacent the side walls of the housing providing opposed contact surfaces, flanges on said contact strips extending over said bosses and being provided with means for attaching conductors thereto, a liquid contact circuit closer between said contacts and having terminals frictionally engaging said opposed contact surfaces, means for supporting the liquid contact circuit closer for rotation about the axes of its terminals, amounting strap secured to said housing for mounting the switch in an outlet box or the like, and means between said mounting strap and said contacts for clamping the contacts against said bosses.

. 24. In an electric switch, a housing having side walls provided with openings and having bosses outside-of said openings facing the top of the housing, contact strips adjacent the side walls of the housing providing opposed contact surfaces, flanges on said contact strips extending over said bosses and being provided with means for attaching conductors thereto, a liquid contact circuit closer between said contacts and having terminals frictionally engaging said opposed contact surfaces, engaging portions on said terminals'and said contact surfaces whereby the circuit closer is supported for rotation about the axis of its terminals, a member secured to the housing, and means between said member and said contacts for clamping the contacts against said bosses.

25. In an electric switch, a liquid contact circuit closer having a liquid containing envelope including a terminal of sheet metal, a sheet metal contact engaging said terminal, and compleing surfaces whereby the circuit closer is rotata-' ble about the axis oi. said terminal, said bearing surfaces being of relatively great diameter compared to the thickness of the metal.

26. In an electric switch, a liquid contact circuit closer having a terminal, and a contact engaging said terminal, said terminal and said contact having hollow thin-walled projections providing interengaging bearing surfaces whereby the circuit closer is supported for rotation, the

diameterof said bearing surfaces being relatively great compared to the wall thickness of said projections,

ROBERT; 1f. SAMZBLESON.

DISCLAIMER 2,142,153.R0bert F. Sambleson, Bridgeport, Conn. ELECTRIC SWITCH. Patent.

dated January 3, 1939. Disclaimer filed October 1, 1940, by the assignee; General Electric Company.

Hereb enters this disclaimer of claims 1 and 5 of said patent.

[ jficial Gazette October 29, 1940.]

DISCLAIMER 2,142,153.Robert F. Sambleson, Bridgeport, Conn. ELECTRIC Swrrcn. Patent. dated January 3, 1939. Disclaimer'filed October 1, 1940, by the assignee, General Electric Company. Hereby enters this disclaimer of claims 1 and 5 of said patent.

[Official Gazette October 29, 1.940.] 

